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Los  Anfc#l*3  i2,   CalifV* 

U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  SOILS— MILTON  WHITNEY,  Chief. 


D    001  108  861    4 

SOIL  SURVEY  OF  THE  SOLOMONSVILLE  AREA, 

ARIZONA. 


BY 


MACY  H.  LAPHAM  and  N.  P.  NEILL. 


[Advance  Sheets— Field  Operations  of  the  Bnrean  of  Soils,  1903.] 

UCLA  SEL/Geology  Collection 


WASHINGTON: 

GOVERNMENT    PRINTING    OFFICE. 

1  9  (.)  4  . 


1 


U.  S.  DEPARTMENT   OF  AGRICULTURE, 

BUREAU  OF  SOILS— MILTON  WHITNEY,  Chief. 


SOIL  SURVEY  OF  THE  SOLOMONSVILLE  AREA, 

ARIZONA. 


BY 


MACY  H.  LAPHAM  and  N.  P.  NEILL. 


[Advance  Sheets— Field  Operations  of  the  Bureau  of  Soils,  1903.] 


WASHINGTON: 

GOVERNMENT    PRINTING    OFFICE. 

1904. 


[Public  Resolution — No.  9.] 

JOINT  RESOLUTION  Amending  public  resolution  numbered  eight,  Fifty-sixth  Congress,  second 
session,  approved  February  twenty-third,  nineteen  hundred  and  one,  "providing  for  the  printing 
annually  of  the  report  on  field  operations  of  the  Division  of  Soils,  Department  of  Agriculture." 

Resolved  by  the  Senate  and  House  of  Representatives  of  the  United  States  of  America  in 
Congress  assembled,  That  public  resolution  numbered  eight,  Fifty -sixth  Congress, 
second  session,  approved  February  twenty-third,  nineteen  hundred  and  one,  be 
amended  by  striking  out  all  after  the  resolving  clause  and  inserting  in  lieu  thereof 
the  following: 

That  there  shall  be  printed  ten  thousand  five  hundred  copies  of  the  report  on  field 
operations  of  the  Division  of  Soils,  Department  of  Agriculture,  of  which  one  thou- 
sand five  hundred  copies  shall  be  for  the  use  of  the  Senate,  three  thousand  copies 
for  the  use  of  the  House  of  Representatives,  and  six  thousand  copies  for  the  use  of 
the  Department  of  Agriculture:  Provided,  That  in  addition  to  the  number  of  copies 
above  provided  for  there  shall  be  printed,  as  soon  as  the  manuscript  can  be  prepared, 
with  the  necessary  maps  and  illustrations  to  accompany  it,  a  report  on  each  area 
surveyed,  in  the  form  of  advance  sheets,  bound  in  paper  covers,  of  which  five  hun- 
dred copies  shall  be  for  the  use  of  each  Senator  from  the  State,  two  thousand  copies 
for  the  use  ot  each  Representative  for  the  Congressional  district  or  districts  in  which 
the  survey  is  made,  and  one  thousand  copies  for  the  use  of  the  Department  of 
Agriculture. 

Approved,  March  14,  1904. 

[On  July  1,  1901,  the  Division  of  Soils  was  reorganized  into  the  Bureau  of  Soils.] 


CONTEXTS 


SfJJr 
Geol. 
Lib. 

S 

An 

L3T1 


Page. 


Soil  Survey  of  the  Solomonsville  Area,  Arizona.     By  Macv  H.  Lapham 

and  N.  P.  Xeill 5 

Location  and  boundaries  of  the  area 5 

History  of  settlement  and  agricultural  devel<  tpment 6 

Climate - 7 

Physiography  and  geology 8 

Soils 10 

Maricopa  gravelly  loam 11 

Gila  fine  sandy  loam 12 

Maricopa  sand - 1-1 

Maricopa  sandy  loam 15 

Maricopa  silt  loam 17 

Pecos  sand - 19 

Riverwash 20 

"Water  supply  for  irrigation - 20 

Underground  and  seepage  water 22 

Alkali  in  soils 24 

Reclamation  of  alkali  land 26 

Agricultural  methods 27 

Agricultural  conditions - 29 


ILLUSTRATIONS. 


PLATE. 

Plate  I.  Alkali  map,  Solomonsville  sheet,  Arizona  (colored  plate) 

text  figure. 
Fig.  1.  Sketch  map  showing  position  of  the  Solomonsville  area,  Arizona 

MAP. 

Soil  map,  Solomonsville  sheet.  Arizona. 


Page. 
24 


SOIL  SURVEY  OF  THE  SOLOMONSVILLE  AREA,  ARIZONA. 

By  MACY   H.  LAPHAM   and  N.  P.  NEILL. 
LOCATION    AND    BOUNDARIES    OF    THE    AREA. 

The  area  with  which  this  report  deals  lies  in  the  southeastern  part 
of  the  Territory  of  Arizona.  It  embraces  about  108  square  miles,  for 
the  most  part  well  irrigated  and  under  a  moderate!}'  intensive  system 


Sketch  map  showing  position  of  the  Solomonsville  area,  Arizona. 


of  agriculture,  lying  along  the  valle}^  of  the  upper  Gila  River.  The 
urea  covers  a  tract  of  land  from  2  to  6  miles  in  width,  extending  north- 
westward from  Solomons ville,  the  uppermost  town  of  importance  in 

5 


6  FIELD    OPERATIONS    OF    THE    BUKEAU    OF    SOILS,   1903. 

the  valley,  to  the  township  line  near  Fort  Thomas.  Above  Solomons- 
ville  the  area  covered  by  the  irrigated  lands  becomes  somewhat  nar- 
rower and  extends  in  a  general  northeaster^  direction  for  a  distance 
of  about  8  miles.  Here  the  valley  suddenly  contracts  to  a  series  of 
narrow  canyons  and  the  head  of  irrigation  is  reached.  Upon  each  side 
the  area  is  bounded  by  arbitrary  lines  running  parallel  to  the  lands 
under  irrigation  and  cutting  the  lines  of  the  bordering  bluifs  and  high 
mesas  near  their  margins. 

The  soil  map  of  this  area  is  published  on  a  scale  of  1  inch  to  the  mile. 
As  no  base  map  was  available  it  was  necessary  to  make  a  plane-table 
survey  of  the  area  in  connection  with  the  soil  work. 

HISTORY   OF    SETTLEMENT   AND   AGRICULTURAL   DEVELOPMENT. 

This  section  of  Arizona  was  undoubtedly  at  one  time  inhabited  by 
prehistoric  races  who  reached  a  higher  state  of  civilization  than  the 
Indians  known  to  the  early  settlers.  They  lived  in  villages  and  culti- 
vated the  soil  with  the  aid  of  irrigation.  Remains  of  their  dwellings, 
irrigation  canals,  implements,  and  pottery  are  abundant.  The  origin 
and  fate  of  these  people  can  only  be  conjectured.  Their  history,  cus- 
toms, and  arts  have  no  place  in  the  legends  of  the  oldest  Indian  tribes, 
and  their  former  occupanc}7  of  the  land  is  shown  onl}r  by  these  scattered 
relics. 

The  Indian  tribes  inhabiting  the  country  at  the  time  of  its  explora- 
tion and  settlement  were  a  nomadic  and  much  less  progressive  race. 
If  they  practiced  agriculture  at  all  it  was  only  in  a  limited  and  crude 
way.  The  Indians  of  this  section  were  mostly  of  the  Apache  tribe, 
and  when,  as  frequently  occurred,  they  took  the  warpath  in  opposition 
to  the  white  settlers  they  were  extremely  cruel  and  formidable  enemies. 

The  mineral  wealth  of  the  surrounding  mountains  was  the  early 
incentive  to  exploration  and  settlement.  The  opening  of  the  mines, 
now  famous  for  the  production  of  copper,  in  the  vicinity  of  Clifton 
and  Morenci,  called  for  a  supply  of  ha3T,  grain,  and  charcoal.  It  was 
to  supply  these  wants  that  the  first  settlers  entered  the  Gila  Vallev-  in 
the  later  seventies  and  took  up  land  about  Solomonsville  and  San  Jose. 

The  northwestern  part  of  the  area  owes  its  settlement  and  reclama- 
tion to  the  Mormons.  These  people  entered  the  valley  in  large  num- 
bers, beginning  about  1880.  They  came  in  families  and  colonies  with 
the  intention  of  founding  permanent  homes,  and  built  up  an  intensive 
s}Tstem  of  agriculture.  The3T  have,  for  the  most  part,  been  very  suc- 
cessful. Small,  well  cultivated  farms  have  .taken  the  place  of  the 
desert,  and  neat  farm  buildings,  often  of  brick,  have  replaced  the  tem- 
porary houses  of  mud  or  canvas.  In  recent  }Tears  the  immigration  of 
Mormons  has  been  somewhat  retarded  and  their  numbers  have  decreased 
on  account  of  their  removal  to  the  Mormon  settlements  of  Mexico. 

A  large  proportion  of  the  lands  of  the  area  have  been  brought  under 


SOIL    SUEVEY    OF    SOLOMONSVILLE    AEEA,   AEIZONA. 


cultivation  within  recent  years,  and  the  limits  of  irrigation  are  at  the 
present  time  being  quite  rapidly  extended.  Progress  in  the  adoption 
of  modern  methods  of  cultivation  and  of  labor-saving  devices  has  also 
been  rapid. 

CLIMATE. 

The  climate  of  this  section  is  essentially  arid,  the  average  annual 
rainfall  being  less  than  10  inches.  This  condition  is  accompanied  by 
low  relative  humidity,  marked  absence  of  clouds  or  fog,  high  maxi- 
mum and  average  annual  temperature,  and  vigorous  wind  movement 
at  certain  seasons  of  the  year — all  factors  most  favorable  to  evapora- 
tion and  intensifying  the  aridity  resulting  from  insufficient  rainfall. 

The  practice  of  agriculture  without  the  aid  of  irrigation  is  not 
attempted  in  this  section,  and  the  success  of  agriculture  depends  to  a 
greater  extent  upon  the  rainfall  in  the  region  of  the  headwaters  of  the 
Gila  River  and  its  tributaries  than  in  the  immediate  vicinity  of  the 
irrigated  lands.  These  streams  head  in  the  mountains  at  a  much 
higher  altitude  than  the  valley,  and  hence  receive  the  rainfall  of  a 
much  more  humid  climate,  the  amount  of  precipitation  increasing  rap- 
idly with  the  elevation. 

The  seasonal  floods,  caused  by  the  mountain  rains  and  the  more  or 
less  uncertain  showers  and  rains  of  the  valley,  occur  during  the  mid- 
dle and  late  summer  months,  sometimes  continuing  through  the  fall. 
During  the  winter  and  spring  the  precipitation  is  slight.  Thunder 
storms  during  the  summer  and  rainy  seasons  are  frequently  accom- 
panied by  severe  dust  storms  and  sometimes  by  hail. 

The  following  table  is  from  records  of  the  Weather  Bureau  sta- 
tions at  Dudleyville  and  Fort  Grant.     The  former  station  lies  a  few 
miles  west  of  the  area  in  Pinal  County,  and  the  latter  in  Graham 
County,  just  outside  of  the  southern  boundary  of  the  survey. 
Normal  monthly  and  annual  temperature  and  precipitation. 


Month. 

Fort  Grant. 

Dudleyville. 

Month. 

Fort  Grant. 

Dudleyville. 

Temper- 
ature. 

Precipi- 
tation. 

Temper- 
ature. 

Precipi- 
tation. 

Temper- 
ature. 

Precipi- 
tation. 

Temper- 
ature. 

Precipi- 
tation. 

January 

February 

March 

April 

o  p 
44.0 
47.0 
52.4 
58.8 
67.9 

Incites. 

0.92 

1.21 

1.13 

3s 

.29 

.65 

3.86 

46.6 
50.  2 
55. 5 

63.3 
71.2 
79.1 
84.9 

Inches. 

1.28 
1.07 
.83 
.45 
.36 
.30 
1.69 

August 

September .. 

October 

November  . . 
December. . . 

Year . . 

77.0 
72.3 
63.5 
51.5 
46.1 

Inches. 

3.22 
1.84 
.91 
.86 
1.52 

°  F. 

82.5 
77.7 
6(1.  2 
55.  7 
48.1 

Inches. 

2.26 

1.20 

.99 

.82 

1.09 

June 

July 

76.9 
79.1 

61.4 

16.85          65.1 

12.34 

The  winters  are  clear  and  mild.  Frosts  are  of  frequent  but  snow 
of  very  rare  occurrence  in  the  valley.  During  the  summer  months 
the  days  are  extremely  hot,  but  the  sensible  temperature  is  greatly 
reduced  by  the  low  relative  humidity.     The  nights  are  generalh'  cool 

9568—04 2 


8  FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 

and  pleasant.  Owing  to  the  frequent  severe  frosts  occurring  in  the 
valley  during  the  winter  season  the  growing  of  citrus  fruits  is  impos- 
sible. The  average  date  of  the  last  killing  frost  in  spring  at  Fort 
Grant  is  April  7;  at  Dudley ville,  March  30;  and  of  the  first  in  fall, 
Fort  Grant,  November  29;  Dudley  ville,  November  11. 

During  the  fall  and  winter  the  wind  movement  is  moderate.  With 
the  advance  of  spring,  however,  the  winds  blow  with  increasing  force 
and  severe  wind  and  dust  storms  often  occur  during  the  spring  and 
summer. 

PHYSIOGRAPHY   AND    GEOLOGY. 

The  mountains  of  this  area  consist  of  rugged  chains  and  spurs, 
often  rising  in  perpendicular  cliffs  and  capped  with  jagged  peaks. 
Onl}r  the  tops  of  the  higher  ranges  are  forested  or  covered  with  other 
than  desert  vegetation.  Between  the  ranges  lie  level  valleys,  usually 
traversed  by  a  stream,  often  of  intermittent  flow.  Spreading  outward 
from  the  base  of  the  mountains  to  the  valleys  below  is  a  succession  of 
evenly  sloping  or  gently  undulating  plains.  These  plains,  formed  of 
mountain  waste  brought  down  by  swiftly  moving  flood  streams,  head 
in  the  narrow  canyons  of  the  mountain  slopes,  from  which  they  extend 
in  broad,  sj^mmetrical,  cone  or  fanlike  deltas.  As  they  recede  from 
the  canyons  the  areas  coalesce,  forming  a  single,  broad  debris  apron 
at  the  foot  of  the  mountains.  The  valleys  have  in  many  cases  been 
filled  to  great  depths  by  this  material. 

The  Gila  Valley  is  almost  wholly  inclosed  by  rugged  mountain 
ranges.  Upon  the  north  and  east  it  is  bounded  by  the  generally  bar- 
ren outlying  peaks  and  hills  of  the  Gila  Range,  through  which  the 
Gila  River  cuts  at  the  Narrows,  some  10  miles  above  Solomonsville. 
Along  the  southwestern  boundary  it  is  inclosed  bj^  the  Pinaleno  Range, 
culminating  in  the  rugged  and  lofty  peak  of  Mount  Graham.  This 
peak  rises  to  a  height  of  over  10,000  feet  above  sea  level,  and  until 
late  in  spring  retains  the  winter  snows  in  its  lofty  canj^ons  and  on  its 
forest-covered  slopes.  To  the  northwest  the  valle}7  is  much  con- 
tracted by  scattered  peaks  and  ranges,  the  highest  of  which  is  Mount 
Trumbull. 

The  mountains  consist  primarily  of  granite,  with  frequent  intrusions 
of  volcanic  rocks,  usually  lavas  of  recent  date.  Upon  the  upper  slopes 
of  the  higher  peaks  springs  and  streams  are  abundant. 

Approaching  the  San  Simon  Valley,  the  southwestern  side  of  the 
Gila  Valley  is  bounded  by  the  undulating  plains  lying  at  the  foot  of 
the  Pinaleno  and  Peloncillo  ranges. 

The  debris  apron  extends  nearly  or  quite  to  the  valley  trough,  being- 
interrupted  only  by  recent  erosion  of  the  valley  streams.  The  agency 
of  the  canyon  streams  in  building  up  this  great  sheet,  composed 
mostly  of  material  derived  from  granitic  and  volcanic  rocks,  is  appar- 
ent.    The  soils  are  usually  of  a  reddish  or  chocolate-brown  color  and 


SOIL    SURVEY    <>F    SOLOMONSVILLE    AREA,   ARIZONA.  9 

of  moderate^  fine  texture.  Near  the  mouths  of  extensive  canyons 
and  washes  occur  deposits  of  sand,  usually  of  coarse  texture.  Through- 
out the  deposits  of  the  foot  slope  gravel  occurs  in  large  and  quite 
uniform  quantities.  The  surface  is  frequently  entirely  covered  with 
tine  angular  gravel  of  volcanic  origin,  which,  when  embedded  in  the 
soil,  forms  a  hard,  smooth  surface.  In  other  positions  the  gravel 
consists  largely  of  granitic  fragments,  with  considerable  quartz,  feld- 
spar, and  other  common  rocks.  Wherever  the  foot  slopes  are  cut  by 
streams  prominent  bluff  and  terrace  lines  are  formed.  These  are 
sometimes  quite  extensive  and  often  very  abrupt.  In  the  vicinity  and 
covering  the  edges  of  these  terraces  gravel  deposits  also  occur,  the 
fragments  varying  in  size  from  that  of  a  pea  to  small,  well-rounded 
bowlders. 

The  terraces  are  often  deeply  cut  by  small  washes  and  canyon 
streams  heading  upon  the  terrace  levels  and  forming  a  secondary  s}Ts- 
tem  of  canyon  mouths  and  fans  upon  the  valley  bottom  below.  Hori- 
zontal beds  of  drab  or  gray-colored  sandstone,  underlying  the  surface 
material  of  the  foot  slopes,  are  f requently  exposed  in  the  deeper*cuts 
along- the  foot-slope  margins.  Strata  of  clays  and  shales  in  advanced 
stages  of  decomposition  often  occur  interbedded  with  the  sandstone. 

The  strata  of  gravel  are  often  cemented  into  a  calcareous  hardpan 
exposed  along  cuts  and  margins  of  the  terraces.  This  material  fre- 
quently caps  the  mesa  lands  and  covers  the  softer  earths  and  rocks 
below. 

The  character  of  the  material  of  the  secondary  foot  slope  is  similar 
to  that  of  the  main  foot  slope  above,  from  which  it  is  derived.  The 
surface  of  the  fans  is  usuall}7  of  gentle  slope  and  covered  only  with 
scattered  cacti  of  various  species,  yucca,  greasewood,  and  various 
other  desert  plants. 

The  river  bottom  or  valley  trough  occupies  a  tract  from  1  to  5  miles 
in  width,  through  which  flows  the  Gila  River.  The  river  course  has 
been  partially  refilled  b}-  alluvial  sediments.  The  Gila  River  and  its 
tributaries  carry  in  suspension  a  vast  amount  of  sediment  which  is 
deposited  in  considerable  quantities  along  the  river  flood  plain  during 
high  water.  The  cutting  away  of  the  stream  banks  as  the  stream 
shifted  from  side  to  side  has  produced  the  level  bottom,  flanked  by 
the  steep  slopes  of  the  terrace-bordered  mesa  lands.  From  the  valley 
trough  the  bottom  extends  outward  with  gentle  slope  to  the  bluff 
lines  marking  the  margins  of  the  mesa  lands.  Small  terraces  of  recent 
origin  frequently  occur  in  the  valley  bottom.  The  material  consists 
of  alluvial  deposits  ranging  from  silts  and  sands  to  coarse  gravel. 
Near  the  base  of  the  terraces  marking  the  valle}-  borders  these  alluvial 
deposits  are  frequently  overlain  by  wash  from  the  mesa  lands  and 
canyon  streams.  Portions  adjacent  to  the  river  channel  are  f  requently 
occupied  by  extensive  deposits  of  fine  river  sands  of  uneven,  wind- 
blown surface  and  covered  with  a  heavy  growth  of  willow  and 
cottonwood. 


10 


FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 


A  considerable  part  of  the  water  supply  comes  from  melting  snow, 
springs,  and  mountain  streams  near  the  source  of  the  Gila  River,  and 
an  important  part  from  the  tributary  Gila  Bonita,  Prieto,  and  Blue 
creeks,  and  the  San  Francisco  River,  all  emptying  into  the  river  above 
Solomonsville. 

San  Simon  River,  which  enters  the  Gila  near  Solomonsville,  is  ordi- 
narily an  insignificant  and  poorly  defined  water  course.  It  drains  a 
large  extent  of  country  known  as  the  San  Simon  Vallej7,  lying  in  the 
southeastern  part  of  the  Territory,  and  is  subject  to  sudden  and 
heavy  floods.  At  such  times  vast  quantities  of  a  very  fine,  heavy  silt 
are  brought  down  and  deposited  in  the  lower  vallej7,  and  in  that  part 
of  the  Gila  Valley  tying  between  Solomonsville  and  Safford. 

SOILS. 

The  extent  and  position  of  the  different  soil  types  of  this  area  are 
shown  in  colors  upon  the  map,  each  color  representing  a  distinct  type 
described  in  the  following  pages.  Sojl  profiles  indicating  the  char- 
acter of  the  soil  to  a  depth  of  6  feet  are  given  on  the  margin  of  the 
map.  The  presence  of  gravel  in  the  soil  in  such  quantities  as  to 
influence  its  texture  and  agricultural  value  is  shown  b}7  symbol. 

The  soils  of  this  area  fall  naturally  into  two  more  or  less  widely 
separated  divisions,  viz,  colluvial  soils  and  alluvial  soils.  In  the  extreme 
and  pronounced  types  the  distinction  is  evident;  with  the  less  pro- 
nounced types  the  soils  of  the  two  divisions  grade  together  by  imper- 
ceptible degrees,  and  the  classification  is  of  a  somewhat  arbitrary 
character. 

The  colluvial  soils  make  up  the  original  foot  slopes  of  the  mountains, 
and  consist  of  mountain  waste  deposited  in  gently  sloping  plains  by 
intermittent  floods  from  cloud-bursts  falling  upon  the  mountain  sides. 
The  soils  of  the  system  of  secondary  fans  previous^  described  are 
also  included  in  this  class.  Under,  the  soils  classed  as  alluvial  fall 
those  formed  by  river  sediment  brought  for  considerable  distances  in 
suspension  and  deposited  by  floods  along  the  river  flood  plain. 

The  colluvial  soils  are  the  Maricopa  gravelly  loam,  Maricopa  sand, 
and  Maricopa  sandy  loam.  The  alluvial  types  are  Riverwash,  Pecos 
sand,  Gila  fine  sandy  loam,  and  Maricopa  silt  loam.  The  following 
table  gives  the  extent  of  each  of  these  types: 

A  reas  of  different  soils. 


Soil. 

Acres. 

Per  cent. 

•25.fi 

Soil. 

Acres. 

Per  cent. 

17,  728 

6,720 
256 

9.7 

12,864  !          18.6 

11,648            16.8 

10,368  j          15.0 

9,600            13-9 

.4 

Maricopa  silt  loam 

69, 184 

Maricopa  sand  v  loam 

SOIL    SUEVEY    OF    SOLOMONSVILLE    AREA,    ARIZONA.  11 


MARICOPA    GRAVELLY    LOAM. 


The  areas  of  the  Maricopa  gravelly  loam  consist  of  remnants  of  the 
original  foot  slope  of  the  mountains.  The  depth  of  this  soil,  except 
in  the  vicinity  of  eroded  areas  where  it  may  be  underlain  by  a  calcare- 
ous hardpan,  is  always  at  least  6  feet,  and  often  much  greater. 

The  Maricopa  gravelly  loam  consists  of  a  chocolate-brown  loam  of  a 
rather  compact,  tine,  silty  texture,  containing  a  considerable  propor- 
tion of  tine,  angular  gravel.  The  soil  usually  becomes  somewhat 
heavier  in  the  lower  part  of  the  profile.  In  exposures  in  the  cuts  and 
washes  so  common  in  areas  of  this  soil  the  subsoil  is  frequently  seen 
to  be  of  a  very  heavy,  compact  nature,  cracking  upon  exposure  to  the 
weather  and  resembling  adobe.  The  fine  earth  material  of  this  soil  is 
somewhat  heavier  in  this  than  in  other  areas  where  it  occurs. 

Before  cultivation  the  surface  of  the  soil  is  compact,  smooth,  and 
often  thickly  strewn  with  small  gravel,  usually  quite  well  rounded.  In 
local  spots  this  gravel  is  almost  entirely  of  volcanic  origin,  often  partly 
embedded  in  the  soil  and  imparting  a  peculiar^  hard,  smooth,  glistening 
surface,  but  the  particles  are  of  small  size  and  would  not  interfere  with 
cultivation.  The  soil  becomes  quite  sticky  when  wet  and  bakes  some- 
what when  puddled  and  dried.  Along  the  margins  of  the  cuts,  washes, 
and  terraces,  and  over  portions  modified  by  erosion,  the  gravel  is  larger 
and  the  quantit}7  greater,  and  the  soil  becomes  lighter  and  more  sandy 
by  loss  of  the  finer  particles  through  erosion.  A  great  part  of  this 
area  along  the  terraces,  or  in  places  of  severe  erosion,  is  rendered  very 
difficult  or  impossible  of  cultivation  by  excess  of  gravel.  Strata  of 
very  hard  and  refractory  hardpan,  similar  to  that  occurring  in  the 
"  Mortar  Beds"  of  the  Tertiary  gravels  of  the  Great  Plains  in  eastern 
Colorado  (see  Soil  Survey  in  the  Arkansas  Valley,  Field  Operations  of 
the  Bureau  of  Soils,  1902),  also  occur  in  the  subsoil  of  these  terrace 
and  eroded  areas.  Each  strata  probably  represents  the  upper  limit  of 
the  water  table  at  some  time  during  the  earl}r  history  of  the  valley. 

Areas  of  the  Maricopa  gravelly  loam  occur  on  the  upper  terraces 
throughout  the  area  surveyed,  generally  forming  the  borders  of  the 
cultivated  valley  lands.  Areas  also  occur  upon  the  mesa  lands.  The 
surface,  except  where  eroded,  is  level  or  gently  sloping.  These  lands 
are,  however,  often  cut  by  narrow  canyons  from  25  to  loo  or  more 
feet  in  depth,  with  steep  or  nearty  vertical  walls.  Small  domelike 
elevations  or  hills,  with  surface  thickly  strewn  with  cobbles  and  gravel, 
frequently  occur  in  the  vicinity  of  the  canyon  mouths. 

Small  seepage  springs,  alkaline  in  character,  sometimes  occur  along 
the  margins  of  the  terrace  borders  upon  the  northern  and  eastern  sides 
of  the  valley.  Fairty  good  natural  drainage  is,  however,  usually 
afforded  by  underlying  gravel  beds. 

This  soil  is  derived  from  the  weathered  debris  of  the  rocks  of  the 
surrounding  mountains.     During  the  processes  of  valley  filling  this 


12 


FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 


material  has  been  distributed  and  modified  by  mountain  torrents  and 
floods.    Subsequent  wind  action  has  in  places  also  modified  the  deposits. 

Small  quantities  of  gypsum  sometimes  occur  in  this  soil.  Some  of 
the  heavier  subsoils  and  the  adjacent  rocks  are  strongly  impregnated 
with  sodium  chloride,  which,  through  percolating  waters,  gives  rise  to 
the  salt  springs  already  mentioned.  Sulphates  are  also  of  common 
occurrence. 

The  Maricopa  gravelly  loam  lies  entirely  above  the  valley  bottom 
and  beyond  the  reach  of  the  irrigating  systems.  It  is  therefore  at 
present  of  no  agricultural  value  except  for  grazing.  The  vegetation 
consists  of  a  growth  of  cacti,  small  flowering  annuals,  yucca,  and  other 
plants  of  the  desert. 

Should  water  be  brought  upon  these  lands  the}T  could,  with  the 
exception  of  the  broken  and  excessively  gravelly  areas,  be  made- to 
produce  all  the  general  farm  crops  of  this  region.  Fruit  should  do 
well  upon  this  soil,  and  the  slight  elevation  should  make  damage  from 
frost  less  likely  than  in  the  valley  lands.  The  irrigation  of  any  portion 
of  these  lands  (barring  the  possibility  of  artesian  irrigation)  is  out  of 
the  question  without  the  construction  of  extensive  storage  reservoirs. 

The  results  of  a  mechanical  analysis  of  the  fine  earth'of  this  soil  are 
given  in  the  following  table: 

Mechanical  analysis  of  Maricopa  (jmrrlhj  loam. 


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8131 

3E.  i  sec.  26,  T.  7  S., 
R.  26  E. 

Brown      gravelly 
loam,  0  to  12  inches. 

0. 25 

6.42 

10.34 

5.72 

8.90 

9.98 

29. 18 

29. 46 

GILA    FINE    SANDY    LOAM. 


The  Gila  fine  sandy  loam  is  a  mellow  sandy  loam  6  feet  or  more  in 
depth,  of  dark  color  and  fine  sand}-  or  silty  texture.  The  coarser 
sands  of  adjoining  t}Tpes  are  sometimes  mingled  with  this  finer  sedi- 
ment, but  this  occurs  only  to  a  slight  extent.  Jn  lower  areas  lying 
close  to  the  course  of  the  Gila  River  it  is  sometimes  less  than  6  feet 
in  depth,  and  is  underlain  by  river  sand  and  gravel.  Gravel  is  of  rare 
occurrence  upon  the  surface. 

This  soil  occurs  in  long,  narrow  bands  lying  near  the  course  of  the 
Gila  River  and  extending  throughout  the  entire  valley.  It  occupies 
the  intermediate  position  between  the  Pecos  sand  and  the  soil  of  the 
higher  valley  slopes.  Small  bodies  less  uniform  in  texture  sometimes 
occur  at  the  base  of  the  terraces  forming  the  valle}7  borders,  or  extend 


SOIL    SURVEY    OF    SOLOMONSVILLE    AREA,    ARIZONA. 


13 


outward  from  the  normal  position  near  the  valle\*  trough.  The  soil 
grades,  often  very  quickly,  into  the  Pecos  sand  and  the  Maricopa  silt 
loam. 

Occupying  the  lower  parts  of  the  valley,  this  soil  type  is  generally 
level  and  has  little  surface  variation,  although  sometimes  slightly 
pitted  and  cut  by  river  flood  channels.  It  usually  lies  several  feet 
above  the  stream  level.  When  not  separated  from  stream  courses  by 
areas  of  other  soil  t}-pes  it  is  set  off  from  the  stream  by  vertically 
eroded  terraces.  In  the  native  vegetation  cottonwood  and  willow  pre- 
dominate. This  soil  does  not  readily  bake  or  puddle,  except  where  it 
lies  next  to  areas  of  the  Maricopa  silt  loam  and  other  soils  containing 
a  considerable  admixture  of  silt  and  clay.  While  it  retains  moisture 
well  and  does  not  leach  as  readily  as  the  Pecos  sand,  it  allows  the 
ready  percolation  of  water.  The  usual  underlying  deposits  of  sand 
and  gravel  furnish  good  natural  drainage.  Artificial  drainage  is  nec- 
essary only  in  a  few  localities  where  seepage  water  has  collected  from 
the  drainage  of  adjacent  soils  or  from  the  use  of  excessive  quantities 
of  water  in  irrigation. 

The  origin  of  this  soil  and  the  agencies  prominent  in  its  formation 
are  similar  to  those  of  the  Pecos  sand,  the  proportion  of  the  finer 
alluvial  material  here  being  considerably  greater. 

The  Gila  fine  sand}-  loam  carries  considerable  mica,  which  greatly 
increases  its  porosity  and  counteracts  the  binding  effects  of  the  heav-^ 
ier  sediments.  The  mineral  plant  foods  are  usually  present  in  suffi- 
cient quantities  and  the  soil  is  usually  rich  in  organic  matter.  Owing 
to  low  position  and  marked  capillary  power  the  soil  carries  small 
quantities  of  alkali  salts.  Except  where  there  is  considerable  seepage 
from  higher  levels  these  are  not  present  in  alarming  quantities. 

This  is  one  of  the  most  fertile  and  valuable  soils  of  the  valley,  pro- 
ducing large  crops  of  wheat,  barley,  and  alfalfa.  It  is  well  adapted 
to  the  culture  of  fruit,  especially  apples,  as  well  as  to  sugar  beets, 
alfalfa,  and  grains,  including  wheat,  barley,  corn,  and  sorghum. 

The  following  table  shows  the  results  of  mechanical  analyses  of  this 

soil: 

Mechanical  analyses  of  Gila  fine  sandy  loam. 


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8129 

Sec.  2,  T.  7  S.,  R. 
27  E. 

Fine  sandy  loam,  0 
to  12  inches. 

0.89 

0.16 

0.34 

0.50 

8.50 

19.  34 

46.98 

24.10 

8130 

Subsoil  of  8129 

Fine  sandy  loam,  12 

.76 

.-18 

2.  32 

2.40 

18.98 

31.16 

33. 22 

11.42 

to  48  inches. 

14  FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 


MARICOPA    SAND. 


The  Maricopa  sand  consists  of  the  coarser  materials  of  the  secondary 
deltas.  Typically  it  is  a  medium  coarse-textured,  sharp  sand,  mainly 
of  quartz  or  feldspar,  light  gray  or  whitish  in  color  and  6  feet  or  more 
in  depth.  Near  the  margin  of  the  soil  areas,  where  it  has  been  washed 
and  blown  over  the  adjacent  types,  the  depth  of  the  soil  sometimes 
becomes  less  than  6  feet  and  the  texture  somewhat  finer,  approaching 
that  of  a  sandy  loam  in  character.  In  the  vicinity  of  the  canyon 
mouths  it  is  often  striated  with  layers  of  micaceous  fine  sand  or  tine 
sand}^  loam,  which  gives  to  the  soil  the  properties  of  a  fine  sandy  loam. 
Such  areas  are,  however,  local  in  character.  It  is  here  also  often  cut 
b}r  streaks  and  beds  of  coarse,  wellworn  gravel  deposited  in  flood  time 
b}T  the  canyon  streams.  These  beds  are  sometimes  cemented  by  cal- 
cium carbonate  into  a  hardpan  similar  to  that  underlying  parts  of  the 
Maricopa  gravelly  loam. 

Gravel  is  a  prominent  feature  throughout  the  greater  portion  of  the 
areas  of  this  type.  The  particles  are  usually  more  or  less  wcrn  and 
well  rounded  and  consist  chiefly  of  fragments  of  quartz,  feldspar,  and 
granite,  although  fragments  of  volcanic  rocks  are  common.  As  the 
outer  margins  of  the  fans  are  approached  the  gravel  gradually  dis- 
appears, the  soil  in  its  nongravelly  phase  sometimes  covering  large 
areas. 

The  Maricopa  sand  in  its  typical  form  occurs  as  long,  narrow  areas 
skirting  the  valley  margins  and  extending  along  the  base  of  the  slopes 
of  the  Maricopa  gravelly  loam,  or  as  broad,  extensive  tracts  extending 
into  the  valle}T  from  the  secondary  fans  and  canyon  washes.  This  type 
is  one  of  the  most  extensive  of  the  soils  in  the  area,  covering  over  25 
per  cent  of  the  total  area.  The  surface  is  usually  level  or  gently  slop- 
ing. In  the  vicinity  of  the  canyon  mouths  it  is  sometimes  cut  by 
channels  of  small,  intermittent  streams.  Along  the  upper  and  middle 
slopes  of  the  fans,  where  exposed  to  the  action  of  strong  winds,  small 
dunes  and  drifts  are  sometimes  formed.  These  are,  however,  not 
extensive  and  are  easily  leveled.  This  soil  in  its  typically  loose,  porous 
condition  is  well  drained  and  at  no  place  is  artificial  drainage  necessary. 

The  Maricopa  sand  is  derived  from  the  coarser  materials  washed 
from  the  terrace  margins  of  the  Maricopa  gravelty  loam  and  the  sand 
of  the  streams  borne  from  longer  distances.  These  materials  have 
been  further  modified  by  wind  action  and  the  boundaries  of  the  type 
are  still  being  shifted  and  extended  b}T  the  strong  winds. 

The  alkali  salts  are  present  in  this  soil  only  in  small  quantities  and 
need  cause  no  apprehension  unless  they  should  accumulate  through 
seepage  from  higher  irrigated  land  or  are  brought  to  the  surface  by 
irrigation  in  the  few  places  where  the  soil  is  shallow  and  underlain  by 
a  heavy,  alkaline  subsoil. 


SOIL    SURVEY    OF    SOLOMONSVILLE    AREA,   ARIZONA. 


15 


Bodies  of  the  Maricopa  sand  lying  adjacent  to  the  gravel-covered 
slopes  of  the  Maricopa  gravelly  loam  and  in  close  proximity  to  canyon 
mouths  often  contain  such  a  large  percentage  of  gravel  as  to  render 
them  unfit  for  cultivation.  Such  areas  are  usually  above  the  canal 
lines  and  are  of  no  agricultural  value  except  for  grazing.  The  lower 
slopes,  where  gravel  occurs  only  as  small  pebbles  and  in  moderate  or 
small  amounts,  or  disappears  altogether,  yield,  under  proper  cultiva- 
tion and  irrigation,  fair  crops  of  alfalfa,  wheat,  and  barley.  This  soil 
is  somewhat  deficient  in  organic  matter,  and  the  practice  of  green  and 
stable  manuring,  with  careful  rotation  of  crops,  is  recommended. 
The  type  is  easily  tilled,  and  with  proper  treatment  should  form 
valuable  land  for  the  production  of  fruit  and  truck  crops. 

There  is  an  upland  phase  of  this  soil  which,  with  the  exception  of 
a  small  area  south  of  Pima,  lies  above  the  present  level  of  irrigation 
and  is  of  value  only  for  grazing. 

The  following  table  shows  the  results  of  mechanical  analyses  of  the 
fine  earth  of  this  type: 

Mechanical  analyses  of  Maricopa  sand. 


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Sec.  20,  T.  7  S.,  R. 
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Gravelly  sand,  0  to 
12  inches. 

0.56 

5.02 

7.68 

7.06 

21.74 

23.58 

26. 38 

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Sec.  22,  T.  7  S.,  R. 
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Subsoil  of  8143 

Coarse  sand,  12  to 
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21.04 

6.86 

MARICOPA    SANDY    LOAM. 


The  Maricopa  sandy  loam  consists  of  a  coarse  grayish  or  brownish 
sandy  loam,  usually  6  feet  or  more  in  depth.  In  the  vicinity  of  the 
canyon  mouths  are  frequent  interlacing  beds  of  coarse  gravel,  river- 
wash,  and  lime-gravel  hard  pan.  Small  deposits  of  fine  micaceous 
sand,  sandy  loam,  and  silt  sometimes  occur.  Gravel  also  occurs  upon 
the  surface,  sometimes  in  excessive  quantities. 

The  bodies  of  this  soil  nearer  the  middle  of  the  valley  floor  and 
covered  by  the  irrigating  systems  are  free  from  gravel,  or  nearly  so. 
Where  gravel  does  occur  it  varies  from  small  pebbles  to  small  bowl- 
ders and  is  similar  in  character  to  that  of  the  Maricopa  sand. 

The  subsoil  of  this  type  is  sometimes  streaked  and  pitted  with  small 
patches  of  the  Maricopa  sand.     Near  its  outer  boundaries  the  soil  is 


16  FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 

sometimes  less  than  6  feet  in  depth  and  is  underlain  by  the  adjacent 
valley  soil,  over  which  it  has  been  spread  by  freshets  or  winds. 

In  point  of  extent  and  agricultural  value  this  is  an  important  soil 
type.  Long,  narrow  bodies  of  the  soil  occur  throughout  the  area 
along  the  margin  of  the  Maricopa  gravelly  loam  and  the  Maricopa 
sand.  More  uniform  and  extensive  bodies  are  found  over  the  base  of 
the  larger  secondary  fans  forming  the  outer  slopes  and  levels  of  the 
valley  floor.  Often  the  fans  consist  almost  wholly  of  this  material,  and 
a  number  of  such  fans  and  washes  frequently  coalesce  into  broad  sheets 
covering  large  areas  along  the  outlying  portions  of  the  valley.  Such 
bodies  occur  in  the  vicinity  of  Safford,  Thatcher,  and  Pima.  On  one 
side  it  grades  into  the  coarse  Maricopa  sand  and  on  the  other  into  the 
Gila  tine  sandy  loam  and  the  Maricopa  silt  loam. 

The  surface  of  this  soil  t}7pe  is  usually  level,  although  sometimes 
pitted  by  erosion  and  occasionall}r  cut  b\-  small  washes.  It  possesses 
good  natural  drainage,  artificial  drainage  of  the  land  being  rendered 
necessary  only  where  seepage  water  from  adjoining  land  has  collected. 
Such  areas  are  at  present  of  very  small  extent. 

In  origin  and  processes  of  formation  this  type  is  very  similar  to  the 
Maricopa  sand,  the  only  difference  consisting  in  the  small  percentage 
of  fine  sand  and  silt  deposits  of  the  Gila  River  that  have  been  added 
to  the  Maricopa  sand. 

Alkali  salts  occur  in  the  Maricopa  sandy  loam  only  to  a  veiy  limited 
extent.  Except  in  small  areas  near  the  soil  boundaries,  where  the 
salts  from  heavier  subsoils  may  accumulate  at  the  surface  under  the 
influence  of  irrigation,  this  alkali  need  cause  no  alarm. 

This  soil  type  is  easily  tilled,  does  not  puddle  or  bake,  and  when 
properly  cultivated  and  fertilized  with  green  or  stable  manure  pro- 
duces excellent  crops  of  grain,  alfalfa,  fruit,  and  vegetables.  It  car- 
ries less  mineral  and  organic  plant  food  than  the  heavier  soils  of  the 
valley  and  is  more  easily  exhausted,  but  the  constant  addition  of  sedi- 
ment from  the  irrigating  water  tends  to  remed}r  this. 

This  type  is  especiall}'  adapted  to  the  growing  of  garden  and  truck 
crops,  tomatoes,  small  and  stone  fruits,  and  apples.  It  is  very  reten- 
tive of  moisture  and  is  considered  one  of  the  most  valuable  soils  of  the 
valle}r.  With  proper  cultivation  sugar  beets  would  probably  do  well 
on  this  soil. 

The  table  following  shows  the  results  of  mechanical  analyses  of 
t}Tpical  samples  of  fine  earth  of  this  soil. 


SOIL    SURVEY    OF   SOLOMONSVILLE    AREA,   ARIZONA. 

Mechanical  analyses  of  Maricopa  sandy  loam. 


17 


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o 

s 

E 

> 

i75 

5 

P.ct. 

P.  ct. 

P.cl. 

P.ct. 

P.r/. 

P.  d. 

P.  <■/. 

P.  ct. 

8139 

SE.  i  sec.  26,  T.  7 
S..R.26E. 

Sandy  loam,  0  to  12 
inches. 

0.47 

3.26 

8.98 

10.48 

25. 06 

15.58 

23. 80 

12. 84 

8141 

Sec.  21,  T.  7  S.,  R. 
26  E. 

Coarse  sandy  loam, 
0  to  12  inches. 

1.07 

1.18 

4.44 

4.44 

14.80 

12. 44 

27.98 

34.68 

8142 

Subsoil  of  8141 

Sandy  loam,  12  to 
72  inches. 

.76 

1.00 

5. 58 

6.10 

25.  80 

18.40 

30.58 

12. 50 

8140 

Subsoil  of  8139.... 

Gravelly  sandy 
loam,  12  to  72 
inches. 

.61 

9.62 

13. 96 

8.26 

11.94 

12. 90 

24.82 

18. 40 

MARICOPA    SILT    LOAM. 


The  Maricopa  silt  loam  is  a  heavy  brownish  silt  loam,  usually  6  feet 
or  more  in  depth.  It  has  an  exceedingly  line  texture,  crumbling-  to 
an  impalpable  powder  when  dry,  but  becoming  very  sticky  when  wet. 
It  is  easity  puddled,  bakes  upon  exposure  to  the  sun,  and  resembles 
in  physical  characteristics  an  adobe  soil.  It  covers  extensive  areas,  is 
of  uniform  texture,  and  erodes  into  vertically  walled  washes  and  bluffs. 
It  often  extends  to  great  depths,  but  is  sometimes  interstratified  at  less 
than  6  feet  with  layers  of  coarse  and  line  sands  and  gravels.  Near  the 
valley  trough  it  is  often  less  than  6  feet  in  depth  and  is  underlain  by 
materials  of  the  Gila  fine  sandy  loam  and  the  Pecos  sand.  Except  as 
very  fine  particles  the  presence  of  gravel  on  the  surface  is  rare.  North 
and  west  from  Solomonsville  the  soil  assumes  a  very  dense,  heavy 
nature,  resembling  the  eastern  clay  soils. 

The  most  extensive  and  typical  areas  of  this  type  occur  along  San 
Simon  Creek,  extending  from  Solomonsville  to  Satford,  and  in  the 
vicinity  of  Matthews.  Other  bodies  occur  in  long,  narrow  strips 
throughout  the  valley.  The  soil  is  easily  distinguished  from  the 
soils  of  coarser  texture.  It  grades  gradually  into  the  Gila  tine  sandy 
loam. 

The  surface  of  this  type  is  usualhy  smooth  and  level,  except  where 
cut  b}T  washes.  The  banks  of  these  washes  are  from  5  to  20  feet  high, 
nearly  vertical,  stand  for  long  periods  of  time,  and  are  distinctive  of 
this  soil  type.  Native  vegetation  is  sparse  and  upon  wind-swept  areas 
is  almost  wanting.  On  the  lower  lying  parts  of  the  areas  there  is  a 
rank  growth  of  willow. 

The  Maricopa  silt  loam  is  very  compact  and  impervious,  percolation 
takes  place  slowly,  and  except  where  underlain  at  6  feet  or  less  by 


18 


FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 


strata  of  sand  or  gravel  the  underdrainage  is  poor.  The  surface  drain- 
age is  also  often  deficient.  A  considerable  proportion  of  the  cultivated 
area  of  this  soil  type  has  been  damaged  by  this  lack  of  drainage  and 
b}^  seepage  from  adjoining  soils,  and  should  be  artificially  drained. 

This  soil  is  formed  by  the  deposition  of  the  heavier  silt  and  alluvial 
material  carried  by  the  Gila  River  and  its  tributaries,  vast  quantities 
of  which  are  brought  down  and  deposited  by  these  streams  in  times 
of  flood. 

The  Maricopa  silt  loam  contains  an  abundance  of  organic  matter  and 
mineral  plant  food.  It  also  carries  normally  in  the  subsoil,  often  at 
great  depths,  large  quantities  of  alkali.  When  localized  within  the 
first  6  feet  of  the  surface  this  may  be,  and  usually  is,  present  in  dan- 
gerous quantities,  and  in  nearly  all  the  areas  of  this  type  which  have 
been  irrigated  for  some  length  of  time  there  has  been  in  many  places 
an  injurious  accumulation  in  the  surface  soil. 

This  soil,  owing  to  its  close  texture,  tendency  to  puddle  and  bake, 
and  sticky  condition  when  wet,  is  somewhat  refractory  and  is  culti- 
vated with  considerable  difficulty.  Deep  plowing,  the  application  of 
straw  or  coarse  stable  manure,  and  frequent  and  thorough  cultivation 
are  necessary  to  improve  the  physical  condition  of  the  land.  In  areas 
damaged  by  seepage  water  or  alkali  this  treatment  should  be  supple- 
mented by  thorough  artificial  drainage.  When  not  damaged  by  alkali 
or  seepage  water,  and  properly  cultivated,  this  soil  yields  heavy  crops 
of  alfalfa  and  grain. 

The  Maricopa  silt  loam  is  best  adapted  to  alfalfa,  wheat,  barley, 
sorgum,  Egyptian  and  Indian  corn,  and  sugar  beets.  In  those  places 
where  the  alkali  salts  exist  in  excess  sorghum,  beets,  and  alfalfa  will 
be  found  to  give  the  best  results. 

The  following  table  shows  the  texture  of  this  soil  type: 


Mechanical  analyses  of  Maricopa  silt  hum 

iC 

c 

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Locality. 

Description. 

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3 

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6 

P.ct. 

P.  ct. 

P.ct. 

P.  <•/. 

P.  ct. 

P.  Ct. 

P.ct. 

P.ct. 

8134 

Sec.  18,  T.  7  S.,  R. 
27  E. 

Heavy  silty  loam,  0 
to  12  inches. 

1.11 

0.00 

0.08 

0.10 

0.86 

2.12 

72. 98 

23.84 

8137 

Sec.  30,  T.  7  S.,  R. 
27  E. 

Heavy  silly  loam,  0 
to  12  inches. 

.54 

1     .10 

.20 

.20 

1.58 

9.10 

62. 14 

25.86 

8136 

Subsoil  of  8134 

Fine  sandy  loam,  48 
to  72  inches. 

.26 

.00 

.10 

.20 

10. 02 

20.78 

52. 98 

15.92 

8135 

Subsoil  of  8134 

Heavy  silty  loam,  12 
to  48  inches. 

1.08 

!   .oo 

.12 

.16 

2.90 

11.42 

61.22 

21.16 

8138 

>  Subsoil  of  8137 

Heavy  silty  loam,  12 
to  72  inches. 

.25 

]     .04 

.06 

.18 

2.10 

5.74 

53. 20 

38.12 

SOIL    SURVEY    OF    SOLOMONS  VILLE    AREA,   ARIZONA.  19 


PECOS    SAND. 


The  Pecos  sand  is  a  type  of  wide  distribution,  having-  been  recog- 
nized by  the  Bureau  of  Soils  in  its  surveys  of  the  Pecos  Valley,  New 
Mexico,  and  the  Salt  River  Valley.  Arizona.  It  consists  of  a  uniform 
fine  river  sand  of  a  light-gray  or  whitish  color,  6  feet  or  more  in 
depth,  except  where  blown  or  washed  over  adjacent  soil  types.  Small 
areas  of  Riverwash,  as  well  as  gravel  and  streaks  and  patches  of  river 
silt  frequently  occur  within  the  limits  of  this  soil  type.  It  is  under- 
lain bjr  sand  and  gravel. 

The  Pecos  sand  occurs  in  one  long,  narrow  area  lying  adjacent  to 
the  Gila  River,  following  the  valley  trough  throughout  the  entire 
area.  It  is  one  of  the  most  easily  recognized  and  uniform  soil  types 
of  the  area  surveyed. 

This  soil  occurs  only  in  the  river  bottoms  and  is  unmarked  by  rock 
outcrops,  bluffs,  or  prominent  terrace  lines.  In  its  natural  condition 
the  surface  is  more  or  less  uneven,  due  to  the  action  of  water  and 
wind,  and  small  dunes  are  still  being  formed.  The  characteristic 
vegetation  near  the  river  channel  consists  of  willow  and  cottonwood, 
while  upon  the  drier  lands  the  prevailing  growth  is  mesquite.  The 
soil  is  of  a  loose,  porous  texture,  and  very  leachy,  and  much  irrigation 
water  is  lost  from  canals  crossing  it. 

The  Pecos  sand  is  derived  from  the  granitic  and  volcanic  rocks  of 
the  mountains.  These  have  weathered  into  finely  abraded  and  water- 
worn  material,  which  remains  in  suspension  in  the  swiftly  running 
water  of  the  river  for  a  considerable  time,  and  is  deposited  as  broad 
sheets  along  the  river  flood  plain  during  times  of  flood.  The  brisk 
winds  of  the  valley  are  constantly  drifting  this  finer  material  about, 
covering  adjacent  soil  formations  and  extending  the  boundaries  of  this 
type.  This  movement  is  greatly  checked  by  the  dense  growth  of 
willow  common  upon  the  moister  parts  of  this  soil. 

Mica  occurs  in  this  soil  in  noticeable  but  not  excessive  amounts. 
Alkali  occurs  in  small  quantities,  but  there  is  not  enough  of  it  to 
impair  the  value  of  these  lands  for  agriculture.  But  a  small  propor- 
tion of  the  Pecos  sand  is  at  present  cultivated,  mainly  because  of  the 
difficult}'  and  expense  of  clearing  off  the  willow,  cottonwood,  and  mes- 
quite, and  leveling  the  land  for  irrigation.  Small  tracts  are.  however, 
b  ing  cleared,  and  with  thorough  cultivation  and  frequent  manuring 
produce  fair  crops  of  grain,  alfalfa,  and  fruit. 

The  Pecos  sand  is  somewhat  deficient  in  organic  matter  and  in  some 
of  the  important  mineral  plant  foods.  Owing  to  its  leachy  character, 
the  supply  of  plant  food  will  become  rapidly  depleted  if  the  soil  is 
not  intelligently  cultivated  and  fertilized.  Frequent  stirring  greatly 
assists  this  soil  to  retain  moisture  during  dry  seasons.  It  is  easily 
cultivated,  and  if  properly  farmed  should  make  an  excellent  soil  for 
truck  crops  and  small  fruits. 


20 


FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,  1903. 


The  following-  table  shows  the  results  of -mechanical  analyses  of  fine 
earth  of  this  soil  type: 

Mechanical  analyses  of  Pecos  sand. 


,_, 

r-( 

o 

O 

a 

a 

=' 

^ 

d 

0 

d 

C 

d 

t-t 

E 

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t-'R 

in 

■O  rj 

o 

C  n 

No. 

Locality. 

Description. 

as 

3 

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ga 

§a 

ba 

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ga 

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P.  rf. 

J',  rt. 

P.  d. 

Pc<. 

P.ct. 

P.  d. 

P.ct. 

P.  c<. 

8132 

Sec.  18,  T.  7  S.,  K. 
27  E. 

Fine    sand,    0    to    12 
inches. 

0.67 

0.04 

0.22 

0.70 

26. 90 

28.  02 

37.22 

6.86 

8133 

Subsoil  of  813? 

Fine   sand,   12  to  36 
inches. 

.48 

.30 

.66 

.86 

22.82 

39.16 

32.96 

3.18 

RIVERWASH. 


Riverwash  consists  of  coarse  sand,  well-rounded  gravel,  and  small 
bowlders,  and  varies  in  depth  from  a  few  inches  to  several  feet.  It 
is  of  small  extent  and  no  agricultural  value  in  this"  area,  occurring  only 
as  a  few  narrow  streaks  in  the  mesa  lands  and  in  areas  of  Maricopa 
sand  and  Maricopa  sandy  loam.  Poorly  defined  areas,  too  small  to  be 
shown  upon  the  soil  map,  frequently  occur  within  the  limits  of  these 
two  soils. 

WATER    SUPPLY    FOR   IRRIGATION. 

The  entire  water  supply  for  irrigation  in  this  area  is  taken  from 
the  Gila  River.  Over  twenty  canals,  the  most  of  them  small  and  of  a 
more  or  less  private  nature,  or  else  operated  in  cooperation  by  those  to 
whom  water  is  supplied,  furnish  water  to  the  valley  lands.  These 
canals  are  well  distributed  throughout  the  entire  area. 

The  largest  and  oldest  of  the  canals  is  the  Montezuma,  constructed 
in  1871,  covering  lands  along  the  southern  part  of  the  area  surveyed. 
Some  of  the  other  more  important  S}Tstems  are  the  San  Jose,  Union, 
Central,  Graham,  Smithville,  Bryce,  Oregon,  and  Fort  Thomas  canals. 

A  considerable  part  of  the  water  of  the  Gila  River  comes  from  the 
melting  snows  in  the  higher  mountains  near  the  headwaters  of  the  main 
stream  and  its  tributaries.  Frequent  rains  and  showers  in  the  higher 
altitudes  supplement  this  supply.  During  the  late  summer  the  rainy 
season  occurs  and  the  supply  is  greatly  augmented  by  floods.  In  gen- 
eral the  water  supply  of  the  area  has  been  satisfactory.  Excessively 
dry  seasons  have  occurred  at  times,  during  which  crops  under  nearly 
all  the  canal  s\Tstems  have  suffered,  but  usually  no  continued  or  wide- 
spread crop  failures  have  occurred.  The  extension  of  the  canal  sys- 
tems and  the  increasing  activity  in  agriculture  are,  however,  beginning 


SOIL    SURVEY    OF    SOLOMONSVILLE    AREA,   ARIZONA. 


21 


to  affect  the  supply,  and  greater  econom\-  in  the  use  of  water  will  be 
necessary  in  the  future.  Several  veiw  important  questions  regarding 
priority  of  rights  claimed  by  rival  cooperative  companies  are  now  in 
litigation. 

The  water  of  the  Gila  River  carries  large  quantities  of  sediment 
and  small,  but  not  necessarily  dangerous,  quantities  of  the  alkali  salts. 
In  the  upper  part  of  the  valley  there  are  usually  less  than  75  parts 
of  solid  matter  to  100,000  parts  water.  Such  water  is  very  good  for 
irrigation  purposes.  The  results  of  a  chemical  anal}\sis  of  a  sample  of 
the  water  taken  from  the  Montezuma  Canal  at  Solomonsville  late  in 
January,  1903,  are  as  follows: 

Analysis  of  water  token  from  the  Montezuma  Canal  at  Solomonsville,  Ariz. 


Ions. 


Calcium  (Ca) 

Magnesium  (Mg) 

Sodium  (Na) 

Potassium  (K) 

Sulphuric  acid  (S04) . . . 

Chlorine  (CI) 

Bicarbonic  acid  (HCO:j) 

Total  solids 


Parts 
per 

100.000. 


6.80 
2.  20 
5.50 
5.  50 
5.50 
14.70 
22.40 


Conventional  combinations. 


62.60 


Calcium  sulphate  (CaS04) 

Calcium  chloride  (CaCl2) 

Magnesium  chloride  (MgCL)  ... 
Potassium  bicarbonate  (KHCOa) 
Sodium  bicarbonate  (XaHCO-j).. 
Sodium  chloride  (XaCl) 

Total  solids 


Parts 
per 

100,000. 


7.80 
12.40 

8.60 

14.00 

19.10 

.70 


62. 60 


Below  Solomonsville,  except  during  periods  of  more  than  average 
flow,  the  river  is  several  times  exhausted  for  irrigation  purposes,  being 
resupplied  by  underflow  and  b}T  seepage  from  surrounding  irrigated 
lands.  As  might  be  expected,  the  alkali  content  of  the  water  increases 
with  the  progress  of  the  river  through  the  valley.  Even  in  the  lower 
part  of  the  valley,  however,  the  percentage  of  alkali  is  not  sufficient 
to  cause  alarm  if  proper  precautions  in  irrigation  and  drainage  are 
taken. 

The  diverting  dams,  headworks,  and  canals  are  usually  constructed 
by  the  farmers  themselves,  and  are  built  as  cheaply  as  possible.  They 
are  often  of  an  unstable  or  temporary  character  and  are  readily  destined 
b}r  floods.  This  is  especially  true  in  the  case  of  the  diverting  dams. 
These  are  generally  built  of  loose  bowlders  and  brush,  and  while  not 
possessing  the  permanency  of  more  expensive  headworks,  are  quickly 
and  cheap hT  replaced. 

The  alluvial  sediments  of  the  Gila  River  are  of  considerable  impor- 
tance as  fertilizer.  Chemical  analysis  shows  this  material  to  be  very 
rich  in  organic  and  mineral  plant  nutrients.  In  places  several  inches 
of  this  sediment  have  been  deposited  upon  the  land  in  the  course  of  a 
few  years,  saving  many  dollars  that  would  otherwise  be  spent  for  fer- 
tilizers.    The  large  percentage  of  sediment  carried  by  the  water  also 


22  FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,    1903. 

causes  trouble  by  rapidly  silting  up  the  canals,  making  frequent  clean- 
ing necessary.  This  may  be  partly  prevented  by  giving  the  canals 
considerable  fall. 

During  recent  years,  owing  to  the  development  of  extensive  mining 
interests  in  the  Clifton  copper  district,  tailings  from  the  leachers  have 
been  carried  into  the  waters  of  the  Gila  through  the  San  Francisco 
River.  This  is  causing  great  alarm  among  the  residents  of  the  Gila 
Valley.  It  is  claimed  that  pumpkins,  chili,  tomatoes,  and  nearly  all 
vines  and  many  vegetables  once  yielding  heavily  can  no  longer  be 
grown.  That  there  is  some  truth  in  this  seems  evident  from  the  fact 
that  such  plants  thrive  until  brought  in  contact  with  the  sediments  of 
the  irrigating  water,  especially  if  such  irrigation  be  excessive.  The 
quantity  of  this  material,  consisting  mostly  of  finely  pulverized  rock, 
is  sufficient  to  impart  a  light  gray  ish  or  milky  color  to  the  water.  These 
conditions  are  most  evident  in  the  upper  part  of  the  valley,  in  the  vicin- 
ity of  Solomonsville  and  Safford.  In  order  to  determine  the  cause  of 
the  trouble  samples  of  the  water  were  collected  from  the  Montezuma 
and  the  San  Jose  canals,  above  Solomonsville,  on  March  23,  1903. 

At  the  laboratories  in  Washington,  where  these  samples  were  sent 
for  analysis,  the  most  delicate  chemical  tests  failed  to  reveal  the  pres- 
ence of  any  injurious  substances  in  the  waters.  Upon  the  examina- 
tion of  the  sediment  collected  from  these  waters,  small  but  unmis- 
takable traces  of  copper  were  detected.  Analyses  of  samples  of  sedi- 
ment thrown  out  from  the  bottom  of  an  irrigation  lateral  had  also 
proved  the  presence  of  small  amounts  of  copper  in  the  river  sedi- 
ments. The  amount  of  the  substance  occurring  in  the  sediment  was 
in  all  cases  very  small,  and  not  sufficient  for  a  quantitative  determina- 
tion. Copper  in  a  soluble  form  is,  however,  very  poisonous  to  plant 
life,  even  in  very  small  quantities.  That  relatively  large  amounts  of 
the  sediment,  when  deposited  about  the  roots  of  growing  plants, 
should  contain  enough  copper  to  prove  injurious  to  crops  would  not 
be  impossible. 

The  question  of  storage  reservoirs  is  important  and  interesting.  It 
is  possible  that  sites  available  for  this  purpose  may  exist  in  the  valley 
narrows  above  the  head  of  irrigation.  Could  such  a  system  be 
installed,  large  areas  of  the  mesa  land  would  be  brought  under 
cultivation. 

UNDERGROUND    AND    SEEPAGE    WATER. 

In  a  few  wells  of  the  area,  hTing  along  the  lower  valley  levels  and 
adjacent  to  the  main  stream  channels,  water  is  encountered  at  a  depth 
of  less  than  10  feet.  Such  cases  are,  however,  comparatively  rare. 
Along  the  higher  levels  and  outer  valley  margins  the  water  table  is 
found  at  a  depth  of  from  50  to  75  feet  or  more.  The  average  depth 
of  wells  extending  only  to  the  first  water-bearing  stratum  is  probably 
from  20  to  30  feet. 


SOIL    SURVEY    OF    SOLOMON SVILLE    AREA,   ARIZONA. 


23 


As  indicating  the  alkali  content  of  the  subsoil,  the  character  of  the 
underground  water  is  important.  In  general  the  well  waters  of  the 
Gila  Valley  carry  large,  often  very  large,  quantities  of  soluble  salts, 
thus  indicating  the  presence  of  an  excess  of  alkali  in  the  subsoil.  In 
a  few  cases  the  deeper  wells,  reaching  to  the  second  or  third  water- 
bearing stratum,  and  cased  to  prevent  the  entrance  of  surface  water, 
supply  water  superior  to  that  from  the  shallower  wells.  In  many 
other  cases,  however,  especially  in  the  central  and  lower  parts  of  the 
valley,  the  water  of  the  deeper  wells  carries  much  more  alkali  than 
those  of  less  depth.  This  seems  to  be  the  case  wherever  the  heavier 
subsoils  extend  to  great  depths.  Many  of  the  well  waters  of  the 
valley  are  unfit  for  domestic  use.  At  Pima  a  boring  was  extended  to 
the  depth  of  over  800  feet  through  heavy  sedimentary  material  in  an 
attempt  to  secure  artesian  water,  resulting  only  in  a  large  supply  of 
underground  water  (not  confined  under  pressure)  inferior  to  the  water 
of  an  adjacent  surface  well,  which  was  itself  unfit  for  domestic  purposes. 

The  results  of  chemical  analyses  of  several  well  waters  of  the  area 

follow: 

Analyses  of  well  waters. 

[Parts  per  100,000.] 


Constituent. 


Ions: 

Calcium  (Ca) 

Magnesium  ( Mg  i 

Sodium  (Xa)  

Potassium  ( K) 

Sulphuric  acid  (S04) 

Chlorine  (CI) 

Bicarbonic  acid  (HC03) 

Conventional  combinations: 

Calcium  sulphate  (CaS04) 

Calcium  bicarbonate  (CaIIC0:i) 
Magnesium  sulphate  (MgS04).. 
Magnesium  chloride  (MgCl)  ... 

Potassium  chloride  ( KC1 ) 

Sodium  sulphate  (Xa._.S04) 

Sodium  bicarbonate  (NaHCO 
Sodium  chloride  (NaCl) 

Total  solids 


No.  18,  sur- 
face well, 
sec.  2,  T.  7 
S.,  R.  27  E. 


6.8 
2.1 
48.6 
9.1 
40.0 
4::.  1 
48.4 


23.1 


17.3 
22.8 
06.7 
58.1 


No.  28,  open 

well,  35 feet 

deep. 


0.6 
2.3 
47.7 
3.7 
27.  8 
30.4 
60.5 


22.4 
11.4 


7.0 
4.3 
83.3 

59.6 


Well  near 
Safford,  43 
feet  deep. 


is.  1 
4.4 
19.3 
1.3 
13.4 
37.9 
48.4 


18.9 
50.9 


17.2 
2.5 


13.9 
39.4 


198. 4 


188.0 


142.8 


Seepage  water  is  abundant,  but  has  collected  to  a  dangerous  extent 
in  only  a  few  localities.  The  accumulation  of  such  water,  either  in 
pools  or  sloughs  or  filling  the  soil  spaces  of  low-lying  and  poorly- 
drained  lands,  is  caused  either  by  leakage  through  the  sides  and  bot- 
toms of  canals  and  laterals,  or  by  excessive  irrigation  of  higher  lying 
lands.  Water  in  excess  of  the  amount  required  by  growing  crops 
percolates  downward,  fills  the  subsoil,  and  finds  its  way  through  the 


24  FIELD    OPEKATIONS    OF   THE    BUKEAU    OF    SOILS,   1903. 

more  porous  substrata  to  lower  levels  and  local  drainage  basins.  In 
this  way  large  areas  of  valuable  land  at  lower  levels  are  damaged,  being- 
converted  into  alkali  flats,  bogs,  or  marshes.  The  effect  of  this  upon 
the  composition  and  distribution  of  the  alkali  salts  of  the  soil  and  upon 
the  valuable  organic  and  mineral  plant  foods  is  important.  Not  only 
does  a  water-logged  soil  lead  to  the  formation  of  alkali  salts  of  the 
most  dangerous  character  and  their  concentration  within  the  zone  of 
root  activity,  but  the  water  leaches  from  the  soil  the  valuable  mineral 
elements,  retards  proper  aeration,  produces  harmful  changes  in  the 
physical  structure  of  the  soil,  and  arrests  the  development  of  the  nitri- 
fying and  other  bacteria  so  important  to  the  growth  of  plants  and  the 
fertility  of  the  soil. 

Small  bodies  of  land,  somewhat  damaged  by  seepage  water,  occur 
along  the  lower  valley  level  throughout  the  area.  The  most  extensive 
area,  and  the  one  subjected  to  the  greatest  injury,  occurs  in  the  Gila 
fine  sandy  loam  and  the  Maricopa  silt  loam,  about  1  mile  north  of 
Thatcher.  Here  is  an  area  of  once  valuable  land,  covering  hundreds 
of  acres,  extending  westward  along  the  river  for  several  miles,  where 
the  water  stands  upon  the  surface  or  is  found  but  a  few  feet  below. 
The  accumulation  of  this  seepage  water  results  from  excessive  irriga- 
tion of  surrounding  lands,  coupled  with  insufficient  natural  drainage. 

Underground  drainage  in  irrigated  regions  has  been  too  long  a  neg- 
lected subject.  It  is  now,  however,  becoming  of  equal  and  in  some 
respects  greater  importance  than  the  drainage  of  lands  in  humid 
regions.  Even  the  digging  of  a  few  open  ditches  through  the  water- 
logged tracts  would  reduce  the  water  content  of  the  land  to  a  great 
degree.  Upon  the  more  badly  damaged  areas  a  system  of  tile  drain- 
age would  prove  of  great  value. 

ALKALI   IN    SOILS. 

The  alkali  of  the  Gila  Valley  is  confined  for  the  most  part  to  the 
Maricopa  silt  loam.  The  areas  in  which  the  salts  prevail  to  a  danger- 
ous extent  occur  only  in  a  half  dozen  or  so  places,  usually  following 
the  boundaries  of  the  Maricopa  silt  loam  and  covering  from  one-half 
square  mile  to  3  square  miles  each. 

The  position  of  these  areas,  and  the  average  salt  content  to  the  depth 
of  6  feet,  may  be  ascertained  by  reference  to  Plate  I.  The  proportion 
of  alkaline  soil  as  compared  with  the  total  area  surveyed  is  consider- 
able. The  damage  thus  far  done  is,  however,  in  many  cases  slight, 
the  alkali  and  seepage  conditions  upon  the  whole  being  very  much 
better  than  in  many  of  the  irrigated  districts  of  the  West.  The  condi- 
tions, however,  demand  careful  attention  to  prevent  an  extension  of 
the  areas  affected  by  seepage  water  and  the  further  deterioration  of 
lands  already  more  or  less  alkaline.     Over  a  considerable  proportion 


Report  of  Bureau  of  Soils. U.S.Dept  Aor.  1903 


-i 

^ 

^ 

g^ 

2| 

£p; 

3g 

^NOI 1 

■fc^  \.20-40\ 

$V ' 

0=0 

5s 

M 

SOIL    SURVEY    OF    SOLOMONSYILLE    AREA,   ARIZONA.  25 

of  the  area  containing-  from  0.20  to  0.40  per  cent  most  of  the  alkali 
exists  in  the  lower  part  of  the  6-foot  section.  Alfalfa,  when  once 
started,  makes  nearly  a  normal  growth  on  these  areas,  and  in  some 
cases  does  well.  In  soils  in  which  the  salt  content  does  not  exceed 
0.40  per  cent,  sugar  beets,  sorghum,  and  alfalfa  may  be  grown  with 
profit;  provided  precautions  are  taken  in  starting  the  crop.  Often  a 
moderately  heavy  irrigation  before  seeding  will  result  in  the  move- 
ment of  the  surface  salts  toward  the  subsoil.  By  the  time  they  return 
to  the  surface  the  crop  may  have  sufficient  stand  and  vitality  to  endure 
the  injurious  effects  of  the  salts.  Even  slight  alkali  accumulations, 
however,  are  alwa\\s  a  source  of  danger,  and  soils  in  which  they  exist 
should  be  carefully  handled. 

Sodium  chloride,  or  common  table  salt,  is  of  common  occurrence  in 
the  Gila  Valley  area  and  forms  a  large  proportion  of  the  alkali  salts 
of  the  region,  both  in  the  soils  and  in  the  underground  waters.  While 
less  harmful  in  its  effect  upon  plant  growth  than  some  of  the  other 
salts,  it  is  in  abnormal  quantities  a  dangerous  substance. 

Sodium  sulphate  also  occurs  here  in  large  amounts,  and  with  sodium 
chloride  forms  by  far  the  greater  proportion  of  the  total  alkali  salts 
of  the  area.  Upon  the  surface  it  sometimes  appears  as  a  white,  pow- 
dery crust,  readily  blown  into  the  air,  and  has  an  irritating  effect  upon 
the  mucous  membrane  of  the  throat  and  nasal  passages. 

These  two  salts  form  practically  all  the  ""white  alkali"  of  this  area, 
the  sulphates,  chlorides,  and  phosphates  of  calcium,  potassium,  and 
sodium,  respectively,  occurring  in  small  amounts. 

Bicarbonate  and  carbonate  of  sodium  are  also  common  alkali  salts, 
appearing  to  some  extent  in  the  Gila  Valley  area.  The  former  is 
classed  with  the  less  harmful  of  the  alkali  salts.  It  may,  however,  by 
giving  rise  to  the  sodium  carbonate,  be  indirectly  capable  of  doing- 
great  injury. 

Sodium  carbonate,  or  "black  alkali."  as  it  is  commonly  called,  is 
one  of  the  most  dangerous  salts.  It  is,  strictly  speaking,  an  "alkali," 
corroding  and  destroying  both  the  humus  or  vegetable  matter  of  the 
soil  and  the  tissues  of  growing  plants.  In  its  effects  it  is  several  times 
more  deadly  than  either  the  chloride,  sulphate,  or  bicarbonate  of  sodium. 
Its  action  in  corroding  and  dissolving  the  organic  matter  of  the  soil 
imparts  to  the  moist  soil  surface,  and  to  pools  of  seepage  water  where 
it  is  concentrated,  an  inky  black  color.  Although  sodium  carbonate 
is  frequently  detected  both  in  the  soil  and  water  of  the  area,  it  occurs 
in  large  or  dangerous  quantities  only  in  a  few  spots,  too  small  to  be 
shown  on  the  map,  where  the  total  salt  content  is  greatest.  Sodium 
carbonate  may,  in  poorly  drained  areas,  be  formed  by  the  evaporation 
of  bicarbonate  solutions  from  the  surface,  carbon  dioxide  being  slowly 
given  off  and  the  salt  remaining  in  the  less  carbonated  form,  or  as 


26  FIELD    OPERATIONS    OF    THE    BUREAU    OF    ROILS,   1903. 

the  "normal  salt.''  Hence  the  matter  of  drainage  becomes  doubly 
imporant  in  areas  in  which  the  comparatively  harmless  bicarbonate  of 
sodium  prevails. 

In  the  Gila  ValW  area  the  subsoils  of  the  heavier  types  carry  in  the 
aggregate  great  quantities  of  the  alkali  salts.  Fortunately,  however, 
natural  drainage  is  good  and  the  practice  of  excessive  irrigation  is  less 
frequent  than  in  many  western  areas.  The  water  table  lies  at  such 
depths  under  the  greater  portion  of  the  area  that  the  movement  of  salts 
upward  takes  place  only  to  a  limited  extent.  The  accumulation  of  the 
alkali  salts  upon  the  surface  results  for  the  most  part  from  evapora- 
tion of  irrigating  water  carrying  in  solution  the  salts  derived  from 
percolation  of  the  upper  portion  of  the  soil  section.  The  water  table 
plays  but  little  or  no  part  in  the  accumulation. 

RECLAMATION    OF   ALKALI   LAND. 

There  is  always  a  tendency  in  irrigated  districts  to  use  a  greater 
quantity  of  water  than  is  actually  necessary.  This  excess,  unless  car- 
ried away  through  efficient  natural  or  artificial  drainage  channels, 
sooner  or  later  results  in  raising  the  water  table.  At  the  present  time 
but  little  of  the  irrigated  lands  of  the  valley  are  in  need  of  drainage. 
Should  future  irrigation  result  in  raising  the  water  table,  however,  as 
is  likely,  trouble  will  ensue,  especially  in  the  heavier  soils.  When 
the  water  approaches  within  6  feet  or  less  of  the  surface  the  limit  of 
safety  is  reached  and  provision  should  at  once  be  made  for  carrying 
away  the  excess  of  water.  Tile  or  open  drains  at  intervals  of  one- 
eighth  or  one-fourth  mile  will  assist  greatly  in  keeping  the  water  table 
below  the  danger  line. 

Among  the  most  prominent  methods  proposed  for  reclaiming  alkali 
lands  may  be  mentioned  the  removal  of  the  crust  by  scraping,  the 
application  of  chemical  correctives,  the  growing  of  alkali-resistant 
crops,  and  drainage.  Of  these  only  the  last  mentioned  is  thoroughly 
effective,  since  it  is  the  onhy  method  which  removes  the  cause  of  the 
trouble.  Some  of  the  other  methods  may,  however,  be  used  with  good 
results  in  connection  with  drainage. 

The  removal  of  the  alkali  salts  by  scraping  the  surface  calls  for 
much  labor  and  must  be  constantly  repeated,  an}-  good  that  may  result 
being  merely  temporary.  This  method  need  receive  little  serious 
consideration. 

The  application  of  gypsum  is  practiced  with  beneficial  results  in 
soils  where  there  occurs  an  excess  of  sodium  carbonate  or  "black 
alkali.'1  In  this  case  chemical  reaction  takes  place,  and  the  injurious 
carbonate  salt  is  changed  into  the  less  injurious  "white  alkali."  This 
method  alone  does  not  remove  the  cause  or  permanently  improve  the 
land,  and  it  is  but  a  question  of  time  until  the  white  alkali  itself  will 
accumulate  in  sufficient  quantities  to  be  destructive  of  plant  life. 


SOIL    SURVEY    OF   SOLOMONSVILLE    AREA,    ARIZONA.  27 

The  utilization  of  alkali  lands  and  the  gradual  removal  of  the  excess 
of  alkali  salts  have  been  attempted  with  partial  success  by  the  growing 
of  certain  alkali-resistant  plants  of  more  or  less  economic  value.  The 
harvesting  of  the  crop  in  the  case  of  such  plants  removes  a  consider- 
able amount  of  the  alkali  salts,  which  have  been  taken  into  the  plant 
tissues  and  cells.  This  method  is  successful  onl}T  to  a  limited  extent, 
and,  like  the  others  mentioned,  it  fails  to  remove  the  cause.  It  is 
worthy  of  notice,  however,  that  some  field  crops  will  thrive  in  the 
presence  of  a  greater  quantity  of  the  alkali  salts  than  others.  This  is 
true  particular^  of  sorghum,  sugar  beets,  and  alfalfa.  Land  upon 
which  the  injur}7  from  alkali  is  slight,  but  sufficient  to  damage  the 
less  resistant  crops,  should  be  used  for  growing  these  hardier  crops. 

But  it  is  thorough  drainage  of  the  land  that  must  be  considered  the 
only  practical  and  efficient  remedy  for  the  reclamation  of  alkali  lands. 
This  alone  removes  the  cause  by  doing  away  with  the  excess  of  seep- 
age water  and  lowering  the  water  table.  It  both  checks  further 
accumulation  and  makes  possible  the  removal  of  the  salt  already  in 
the  surface  soil.  A  system  of  open  drains  will  do,  but  lines  of  tile  at 
frequent  intervals  are  not  only  more  efficient,  but  are  no  hindrance  to 
cultivation,  and  are  permanent.  The  intervals  between  the  drains 
will  vary  with  the  rate  of  flow  of  water  through  the  soil,  and  can  best 
be  determined  in  an  area  by  experiment  on  a  small  scale.  The  depth 
should  be  such  as  to  keep  the  water  table  below  the  danger  line, 
which,  in  this  area,  is  not  less  than  6  feet. 

The  drainage  of  large  areas  into  the  Gila  River  might,  in  time  of 
low  water,  increase  the  salt  content  of  its  water  to  such  an  extent  as 
to  impair  its  fitness  for  irrigation.  But  with  the  gradual  extension 
of  drainage  through  the  limited  area  requiring  it  in  this  district  the 
effect  would  be  negligible. 

After  the  installation  of  the  drainage  s3Tstem  the  salts  should  be 
removed  by  washing  them  out  through  the  drains  by  frequent  flooding 
of  the  land.  The  water  should  be  added  to  a  depth  of  3  or  -i  inches, 
and  maintained  at  that  depth  as  long  as  possible  or  until  the  land  is 
sufficiently  sweetened  to  allow  the  growing  of  crops.  Occasional  flood- 
ing with  larger  quantities  of  water  is  less  effective.  The  cultivation 
of  the  soil  between  floodings  should  be  very  thorough,  deep  plowing 
and  frequent  stirring  being  very  important.  As  soon  as  enough  salt 
is  removed  to  allow  seed  to  germinate  the  growing  of  the  more  alkali- 
resistant  crops  should  be  begun,  and,  as  the  reclamation  proceeds, 
those  less  resistant  should  be  gradually  introduced. 

AGRICULTURAL   METHODS. 

The  general  agricultural  practice  of  the  area  is  careful  and  intelli- 
gent, but  there  are  many  instances  of  wasteful  and  slovenly  methods. 
The  cultivation  has  changed  gradually  from  an  extensive  to  a  more 


28  FIELD    OPERATIONS    OF   THE    BUREAU    OF    SOILS,    1903. 

intensive  system,  with  a  decrease  in  the  size  of  farms  and  the  wider 
introduction  of  irrigation.  In  some  cases  an  incongruous  mixture  of 
the  two  s}Tstems  is  seen,  the  most  frequent  deficiency  being  in  the 
matter  of  the  preparation  of  the  land.  Where  grain  is  grown  the 
plowing  often  consists  of  merely  scratching  the  surface  of  the  soil 
with  a  harrow.  Upon  the  lighter  soils,  following  corn  or  some  other 
closely  cultivated  crop,  this  might  be  sufficient,  but  in  the  heavier  soils 
the  seeding  of  grain  upon  alfalfa  stubble  or  pasture  land  in  this  man- 
ner is  a  mere  makeshift  such  as  deserves  no  place  under  any  system 
of  agriculture.  Deficient  preparation  and  cultivation  renders  the  soil 
compact  and  increases  evaporation  and  the  accumulation  of  alkali, 
makes  it  difficult  of  aeration  and  root  penetration,  and  hinders  the 
formation  of  plant  food. 

More  care  is  often  taken  in  harvesting  and  marketing  the  crop  than 
in  raising  it.  Alfalfa  is  the  principal  crop  of  the  valley.  Three  and 
sometimes  four  cuttings  are  obtained,  yielding  from  4  to  6  tons  per 
acre.  This  is  usually  baled  and  shipped  out  of  the  area,  bringing 
about  $10  a  ton  loaded  on  the  cars.  The  cost  of  cutting,  stacking, 
and  baling  should  not  greatly  exceed  $2  a  ton,  and  the  hay  will  usually 
bring  $5  a  ton  in  the  stack. 

Corn,  wheat,  and  barley  are  also  important  crops  in  this  area.  Corn 
is  usually  planted  in  midsummer  and  harvested  in  October,  and 
frequently  follows  a  crop  of  wheat  or  barley.  In  favorable  seasons 
wheat  yields  from  30  to  40  bushels  per  acre  and  there  is  a  good  demand 
for  the  grain  at  fairly  high  prices  for  local  milling  purposes.  The 
old-established  Sonora  variety  is  generall}7  grown  and  is  sown  late  in 
the  season.  The  White  Russian  variety  is  grown  to  some  extent  and 
is  sown  in  the  early  fall.  The  former  variety  is,  however,  most  com- 
monly raised,  being  more  resistant  to  drought.  The  grain  is  of  good 
weight  and  makes  excellent  flour. 

The  use  of  commercial  fertilizers  is  very  limited;  the  use  of  stable 
and  green  manures  is  common,  but  might  be  greathr  extended  with 
beneficial  results.  The  rotation  of  crops  receives  much  less  attention 
than  it  should. 

Irrigation  of  the  grains  and  alfalfa  is  mainly  by  flooding  in  rectan- 
gular or  contour  checks.  Irrigation  immediately  after  seeding  is  usu- 
ally avoided  when  the  water  carries  much  sediment,  as  this  sometimes 
forms  a  close,  compact  la}Ter  over  the  seed  bed,  through  which  the 
37oung  plants  make  their  way  with  difficulty.  The  fruits,  vegetables, 
and  similar  crops  are  irrigated  by  the  furrow  method.  With  this 
method  the  alkali  salts  have  a  tendency  to  accumulate  in  the  eleva- 
tions over  which  the  water  does  not  flow.  Irrigation  by  flooding, 
coupled  with  artificial  drainage  when  necessary,  and  deep  and  fre- 
quent plowing  and  cultivation,  should  be  the  general  practice. 


SOIL    SURVEY    OF    SOLOMONSVILLE    AREA,   ARIZONA.  29 

AGRICULTURAL   CONDITIONS. 

The  farming  class  of  the  Gila  Valley  is  made  up  of  Americans  and 
Mexicans,  possessing-  various  degrees  of  intelligence,  education,  ambi- 
tion, and  knowledge  of  agriculture.  It  is  thus  but  natural  that  there 
should  be  varying  degrees  of  success  and  prosperity.  In  farming,  as 
well  as  in  business  enterprises  throughout  the  valley,  there  have  been 
many  failures.  This  has  in  both  cases  resulted  from  overstocking,  lack 
of  intelligent  direction,  indiscreet  speculation,  endeavor  to  promote 
prosperity  by  indulging  in  "boom'1  methods,  and  the  inflation  of 
values,  or  the  want  of  persistent  effort.  Many  of  the  oldest  settlers 
have  left  the  area  to  make  their  homes  in  other  parts  of  the  country, 
but  this  has  not  alwa}ys  been  from  failure  or  dissatisfaction. 

At  present  the  agricultural  industry  is  making  a  natural  if  slow 
growth,  and  the  agricultural  classes  may  be  said,  upon  the  whole,  to 
be  in  a  prosperous  state. 

The  farms  usually  contain  160  acres  or  less.  In  the  more  thickly 
settled  parts  of  the  area,  especially  in  the  Mormon  settlements,  small 
farms  and  intensive  cultivation  are  the  rule.  Here  a  farm  of  '40  acres 
is  considered  large.  But  few  farms  are  rented.  A  remarkable  free- 
dom from  mortgage  and  other  indebtedness  among  the  farming  class 
exists  here.  Tax  rates  would  in  the  East  be  considered  excessive,  but 
this  is  partly  compensated  for  by  the  low  valuation  of  property  and 
the  relatively  high  prices  for  farm  produce.  There  is  a  growing 
tendency  to  improve  the  farm  stock,  to  erect  more  substantial  farm 
buildings,  and  to  render  farm  life  more  attractive.  The  farm  dwel- 
lings are  of  all  grades,  from  the  rude  thatched  huts  of  the  Mexican 
laborers  to  the  pretentious  brick  houses  of  the  richer  farmers. 

The  farm  labor  is  usually  satisfactory  and  efficient  in  character  and 
the  wages  not  excessive,  considering  the  rate  of  wages  paid  in  the 
trades  and  arts  in  this  section,  the  average  being  $30  a  month  with 
board. 

Wheat,  barley,  alfalfa,  and  corn  are  the  principal  field  crops  of  the 
area.  Oats  do  not  mature  well  and  are  but  little  grown.  Sorghum  is 
raised  to  some  extent  and  is  used  in  fattening  cattle.  Fruit  growing- 
has  in  the  past  attracted  little  attention,  but  is  now  increasing  in 
importance  and  is  likely  to  become  an  important  industry  in  this  area. 
The  growing  of  early  fruits — peaches,  apricots,  almonds,  etc. — is 
attended  with  considerable  risk,  owing  to  the  late  spring  frosts. 
Apples,  plums,  and  cherries  are  more  hardy,  yield  abundantly,  and 
find  ready  market.  The  outlook  for  the  apple  industry  is  especially 
favorable.  The  fattening  of  lambs,  hogs,  and  cattle  upon  the  rich 
alfalfa  hay  and  pasture  is  an  important  industry,  and  when  intelli- 
gently followed  is  a  source  of  handsome  profit.  Raising  poultry  offers 
tempting  inducements  to  the  intelligent  and  experienced  breeder.     The 


30  FIELD    OPERATIONS    OF    THE    BUREAU    OF    SOILS,   1903. 

general  neglect  of  this  industry,  the  absence  of  cold  winters,  and  the 
eagerness  with  which  eggs  and  poultry  are  sought  in  the  market  make 
this  an  inviting  opening.  Truck  farming  is  another  neglected  industry 
which  is  capable  of  profitable  development.  Large  areas  of  light, 
warm,  early  soils  occur,  which  with  proper  manuring,  irrigation,  and 
cultivation  could  be  made  to  3neld  large  returns  in  early  vegetables. 
It  is  believed  that  b}r  the  use  of  a  cheese-cloth  or  canvas  covering, 
such  as  is  used  in  parts  of  Florida,  lettuce,  onions,  cabbages,  tomatoes, 
radishes,  and  other  vegetables  could  be  placed  upon  the  market  nearly 
the  year  around. 

A  series  of  important  experiments  in  the  culture  of  the  sugar  beet 
has  been  carried  on  in  this  area  by  the  Arizona  Agricultural  Experi- 
ment Station.  Some  of  the  soils  of  the  area  are  admirabty  adapted 
to  this  crop,  and  good  average  yields  with  a  fairly  high  sugar  content 
and  percentage  of  purity  are  obtained.  While  the  results  are  less 
gratifying  than  in  some  of  the  great  sugar-beet  sections  of  California 
and  Colorado,  they  are  sufficiently  promising  to  interest  capital.  This 
bulky  product  can  not,  however,  be  profitably  shipped  except  for  short 
distances,  and  the  establishment  of  this  industry  will  depend  upon  the 
erection  of  a  factoiy  near  the  source  of  supply.  It  is  worthy  of  note, 
however,  that  growing  sugar  beets  as  a  food  for  fattening  sheep  and 
cattle  is  now  of  considerable  importance  in  other  localities,  where 
feeders  are  ottering  as  good  prices  as  the  sugar  factories. 

In  the  attempt  to  discover  special  crops  for  this  section,  a  trial  of 
some  of  the  more  drought-resistant  macaroni  wheats  should  be  made. 

In  the  more  remote  parts  of  the  valley  marketing  the  crops  is 
laborious  and  expensive,  as  farm  produce  has  often  to  be  hauled  long 
distances  over  rough  or  sandy  roads.  The  entire  area  is  traversed  by 
the  Globe,  Gila  Valley  and  Northern  Railway,  but  shipments  by  rail 
are  very  costly,  owing  to  high  freight  rates.  In  this  respect  this  por- 
tion of  the  Southwest  is  unfortunate,  and  improvement  in  shipping 
facilities  is  badly  needed. 

The  valle}1,  is  as  a  whole  thickly  settled.  The  most  important  towns 
within  the  area  surveyed  are  Solomonsville,  Safford,  Thatcher,  and 
Pima.  Local  markets  are  found  in  all  these  places  for  farm  and 
garden  produce.  A  part  of  this  goes  to  supply  the  adjacent  mining 
camps  and  military  posts.  With  the  growth  of  an  intensive  system  of 
agriculture,  improvement  in  methods  of  irrigation,  cultivation,  and 
drainage,  and  the  recognition  of  the  adaptability  of  soil  and  climate  to 
special  crops,  the  Gila  Valley  is  destined  to  assume  great  importance 
in  the  Territory.  The  lands  of  the  Salt  and  Gila  river  valleys  produce 
practicall}T  all  the  crops  grown  in  Arizona. 


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